Organic light emitting elements are vulnerable to moisture and/or oxygen. Organic light emitting elements may suffer from delamination at an interface between a metal field and a light emitting layer due to moisture. The organic light emitting elements may have high resistance due to oxidation of metals and may suffer from degradation of organic materials in the light emitting layer due to moisture and/or oxygen. The organic light emitting element may suffer from deterioration in light emission property due to oxidation of the light emitting layer or the metal field by outgassing inside or outside the organic light emitting elements. Thus, the organic light emitting element must be encapsulated by an encapsulation composition capable of protecting the organic light emitting element from moisture and/or oxygen.
The organic light emitting element may be encapsulated by an encapsulation layer having a multilayer structure in which an organic layer and an inorganic layer are alternately stacked one above another. The inorganic layer may be formed by plasma deposition. However, the organic layer may be etched by plasma. Etching may deteriorate an encapsulation function of the organic layer and provide adverse influence on formation of the inorganic layer. The organic layer is formed in contact with the inorganic layer. As a result, the organic light emitting element may suffer from deterioration in light emitting property and reliability.
The organic layer may be formed by deposition or ink jetting. When the corner of the organic layer is exposed to the corner of an encapsulation layer without protection, an encapsulation property which protects the organic light emitting element from moisture and/or oxygen may be deteriorated. In addition, when the organic layer is formed by ink jetting, an encapsulation composition for an organic layer in a liquid state may spread to a light emitting area or outside of a substrate, thereby thickening the edge of the encapsulation layer.
The background technique of the invention is disclosed in Korean Patent Laid-Open Publication No. 2011-0071039.